The Geographic and Contextual Measures Core (GCMC) will provide cutting-edge support to investigators associated with the Center for the collection, management, and interpretation of geographic and contextual factors. Assistance is also available in several other specialized areas including environmental epidemiology, social and behavioral epidemiology, Geographical Information Systems (GIS), and digital phenotyping. Core faculty and staff will advise investigators on data management issues, availability of large-scale, high-resolution geographic and contextual data sources, and the use of smartphone applications, and will facilitate training for Center members, graduate students, and fellows working on Center-related projects. Providing these services via a core facility will allow us to build and maintain specialized resources while drawing on the broader resources available through the Departments of Environmental Health, Social and Behavioral Sciences, and Biostatistics, and the Center for Geographic Analysis (CGA) at Harvard. The GCMC will also collaborate directly with the Center's Community Engagement Core (CEC). Having a core facility also provides us with the necessary infrastructure to support educational activities such as seminars and workshops of relevance to Center investigators. GCMC faculty and researchers are experts in many fields of study and actively engage in research directly related to the Center's new theme of re-envisioning an expanded definition of the environment.